2016 Comprehensive Update of the Banff Working Group on Liver Allograft Pathology: Introduction of Antibody-Mediated Rejection

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.

Estimating surface NO2 and SO2 mixing ratios from fast-response total column observations and potential application to geostationary missions

Total-column nitrogen dioxide (NO₂) data collected by a ground-based sun-tracking spectrometer system (Pandora) and an photolytic-converter-based in-situ instrument collocated at NASA's Langley Research Center in Hampton, Virginia were analyzed to study the relationship between total-column and surface NO₂ measurements. The measurements span more than a year and cover all seasons. Surface mixing ratios are estimated via application of a planetary boundary-layer (PBL) height correction factor. This PBL correction factor effectively corrects for boundary-layer variability throughout the day, and accounts for up to ≈75 % of the variability between the NO₂ data sets. Previous studies have made monthly and seasonal comparisons of column/surface data, which has shown generally good agreement over these long average times. In the current analysis comparisons of column densities averaged over 90 s and 1 h are made. Applicability of this technique to sulfur dioxide (SO₂) is briefly explored. The SO₂ correlation is improved by excluding conditions where surface levels are considered background. The analysis is extended to data from the July 2011 DISCOVER-AQ mission over the greater Baltimore, MD area to examine the method's performance in more-polluted urban conditions where NO₂ concentrations are typically much higher.

Familial idiopathic pulmonary fibrosis in association with bone marrow hypoplasia and hepatic nodular regenerative hyperplasia: a new "trimorphic" syndrome

This is the first report of familial idiopathic pulmonary fibrosis associated with hepatic nodular regenerative hyperplasia and bone marrow hypoplasia. Four members of one family presented with this triad of organ dysfunction. The response to immunosuppressive treatment was poor and all four members succumbed to the disease processes. The current literature is reviewed and mechanisms that could have been involved in the development of this new syndrome are proposed.

Haematological malignancies presenting with acute liver injury: a single-centre experience

INTRODUCTION

Early recognition and identification of the underlying cause of acute liver injury (ALI) is crucial in instituting medical treatment and assessing the need for liver transplantation. Haematological malignancies have been reported to present as ALI with progression to acute liver failure but experience is limited.

AIM

Review our experience of ALI secondary to haematological malignancies.

PATIENTS AND METHODS

Patients admitted to the liver unit with ALI secondary to a haematological malignancy between 1996 and 2006 were identified. A retrospective review was made of their case notes and our database.

RESULTS

Of the 752 cases of ALI, six cases of ALI secondary to haematological malignancy were identified. Common features were a prodromal illness (median duration of 5 weeks; range 2-6 weeks) and jaundice (median bilirubin 208 micromol/l; range 112-238 micromol/l). The majority of patients (5/6) had hepatomegaly. Liver biopsy was performed in two patients and confirmed the diagnosis in both cases. In other cases, the diagnosis was made following lymph node biopsy (1), bone marrow examination (2) or from post-mortem examination (1). Median time from jaundice to encephalopathy was 12 days; range 1-22 days. A single patient underwent liver transplantation but died in the immediate post-operative period. All patients died soon after admission with a median survival of 8 days (range 3-26 days).

CONCLUSION

Haematological malignancy should be considered in ALI patients presenting with a prodromal illness, jaundice and hepatomegaly. Biopsy is essential to confirm the diagnosis but the benefit of definitive therapy such as chemotherapy and/or transplantation in this setting is unclear and survival is poor.

IL-18 is upregulated in the kidney and primes neutrophil responsiveness in ANCA-associated vasculitis

In antineutrophil cytoplasm autoantibody (ANCA)-associated systemic vasculitis (ASV), autoantibody-induced neutrophil activation is believed to cause organ damage. In vitro, tumor necrosis factor alpha (TNFalpha) primes neutrophils for ANCA stimulation and TNFalpha blockade has been successfully used to treat ASV. Nonetheless, irreversible organ damage can still occur, suggesting that other cytokines may circumvent TNFalpha blockade. We report that interleukin (IL)-18 deposition, as assessed by immunoperoxidase staining, is increased in renal biopsies from ASV patients. Immunofluorescence microscopy demonstrated that podocytes are the predominant glomerular IL-18-positive cell type, whereas in the interstitium, myofibroblasts, distal tubular epithelium, and infiltrating macrophages stained for IL-18. In vitro, IL-18 primed superoxide production by ANCA-activated neutrophils comparably to TNFalpha. IL-18-primed, ANCA-induced superoxide production was unaffected by anti-TNFalpha antibody, which abrogated TNFalpha priming. Furthermore, TNFalpha and IL-18 phosphorylated neutrophil p38 mitogen-activated protein kinase (MAPK), but IL-18-mediated p38 MAPK phosphorylation was unaffected by anti-TNFalpha antibody. The p38 MAPK inhibitor, SB20358, reduced IL-18-primed, ANCA-induced superoxide production in a concentration-dependent manner. ANCA-induced superoxide release was also sensitive to the Leukotriene B4 (LTB4) inhibitor MK-886. IL-18 priming was not associated with increased ANCA antigen expression on isolated neutrophils. We conclude that IL-18 is likely to be important for neutrophil recruitment and priming in ASV. Therapies targeting single priming agents may have limited efficacy in controlling disease.

Localisation of members of the vascular endothelial growth factor (VEGF) family and their receptors in human atherosclerotic arteries

BACKGROUND

Vascular endothelial growth factor (VEGF) mediates endothelial cell mitogenesis and enhances vascular permeability. The existence of single or multiple VEGF isoforms and receptors suggests that these proteins may have overlapping but distinct functions, which may be reflected in their cell expression and distribution.

METHODS

The localisation of VEGFs A-C and their receptors (VEGFRs 1-3, respectively) in 30 fresh human atherosclerotic arteries, 15 normal uterine arteries, and 15 saphenous veins using immunohistochemistry and western blotting.

RESULTS

Saphenous veins showed no staining for VEGF-B or VEGFR-2. Smooth muscle cells (SMCs) showed the strongest staining for VEGF-A, VEGF-B, VEGFR-1, and VEGFR-2 in all specimens. Conversely, VEGFR-3 and VEGF-C were predominantly localised to the endothelial vasa vasorum in normal arteries, whereas medial SMCs showed the strongest staining in atherosclerotic arteries. Western blotting showed variations in VEGF protein localisation, with lower amounts of VEGF-B and VEGF-C in saphenous veins, compared with arterial tissue. Amounts of VEGF-C were lower than those of VEGF-A and VEGF-B in all specimens.

CONCLUSION

This study provides direct evidence of the presence of VEGF proteins and receptors in human physiology and pathology, with variations in both the amounts of VEGF proteins expressed and their cellular distribution in normal arteries compared with atherosclerotic arteries. The presence of VEGFs A-C and their receptors in normal arterial tissue implies that VEGF functions may extend beyond endothelial cell proliferation. Reduced VEGFR-2 staining in atherosclerotic arteries may have implications for the atherosclerosis process and the development of vascular disease and its complications.

State-dependent responses of two motor systems in the crayfish, Pacifastacus leniusculus

The expression of both swimmeret and postural motor patterns in crayfish (Pacifastacus leniusculus) were affected by stimulation of a second root of a thoracic ganglion. The response of the swimmeret system depended on the state of the postural system. In most cases, the response of the swimmeret system outlasted the stimulus. Stimulation of a thoracic second root also elicited coordinated responses from the postural system, that outlasted the stimulus. In different preparations, either the flexor excitor motor neurones or the extensor excitor motor neurones were excited by this stimulation. In every case, excitation of one set of motor neurones was accompanied by inhibition of that group's functional antagonists. This stimulation seemed to coordinate the activity of both systems; when stimulation inhibited the flexor motor neurones, then the extensor motor neurones and the swimmeret system were excited. When stimulation excited the flexor motor neurones, then the extensor motor neurones and the swimmeret system were inhibited. Two classes of interneurones that responded to stimulation of a thoracic second root were encountered in the first abdominal ganglion. These interneurones could be the pathway that coordinates the response of the postural and swimmeret systems to stimulation of a thoracic second root.

Apparent loss of 2H4+ T cells in peripheral blood lymphocytes of normal donors: a 2H4-specific artefact unique to T cells

The antigenic cluster designated CD45R is recognized by a family of monoclonal antibodies. However, one of those most frequently used because of its commercial availability is 2H4. In a series of experiments we show that 2H4 immunofluorescence is almost completely lost from CD4+ or CD8+ T cells of human origin if they are fixed after staining with 2H4. Loss of fluorescence intensity of the total population of 2H4+ lymphocytes and nearly complete quantitative loss of CD45R+ T cells is observed after fixation. This apparent loss of CD45R as detected by 2H4 is not seen if other CD45R-specific monoclonal antibodies are used. Fixation of B cells previously stained with 2H4 gives rise to slightly diminished fluorescence intensity, but no reduction in number of 2H4+ B cells. This appears to be due to a lower antigen density on T cells as compared to B cells. The effect is unique to 2H4, as other monoclonal antibodies recognizing CD45R, while exhibiting a decrease in fluorescence intensity after fixation, still unequivocally detect CD45R+ CD4+ or CD8+ T cells. The effect is restricted to human T cells, as primate lymphocytes, fixed after staining with 2H4, show no loss in fluorescence intensity. We conclude that if it is necessary to fix human T cells after fluorescent staining, the use of CD45R-specific antibodies other than 2H4 is mandatory.